自适应灰度多段线性变换的FPGA实现

Implementation design of adaptive multistage linear gray transformation based on FPGA

为了解决在弱光照条件下,采集系统采集回的图像对比度低的问题,提出采用多段式线性灰度变换的方法来进行图像增强处理。该方法首先在FPGA中统计一副图像的灰度直方图,然后根据直方图特点,自动生成映射函数,并进行灰度映射运算。实验结果表明此方法满足实时性要求且处理后的图像动态范围增加,对比度明显提高,对弱光照条件下采集的图像具有较好地增强效果。

Under the condition of weak illumination,aiming at the problem of low contrast of the image captured by the acquisition system,a method of multi-segment linear gray transformation is proposed to enhance the image.Firstly,the gray histogram of image is counted through the FPGA.Then,according to the characteristics of the histogram,the mapping function is automatically generated and the gray mapping operation is performed.The experimental results show that this method meets the real-time requirement and the dynamic range of the processed image is increased,and the contrast of the processed image is improved obviously.The design has a good enhancement effect on the image acquired in wake light.